Fine media mill with improved disc

Abstract

An agitator with a rotatable axial shaft with a plurality of grinding discs connected generally perpendicular to the shaft is provided having at least one grinding disc with an axially extending pin spaced radially outwardly from the shaft and radially inwardly from a peripheral edge of the disc. The pin is aligned with a smooth surface on a next adjacent disc.

1. An agitator mill for grinding a product, comprising:
 a rotatable axial shaft; 
 a first grinding disc having a peripheral edge and an outer diameter connected to said shaft in a generally perpendicular orientation, wherein said first grinding disc comprises a first axially extending pin positioned radially outward from said rotatable shaft and radially inward from said peripheral edge of said first grinding disc; 
 a second grinding disc having a peripheral edge connected to said shaft in a generally perpendicular orientation at a spaced apart distance from said first grinding disc; and 
 grinding media that grinds the product, 
 wherein said first axially extending pin is aligned with a smooth surface of said second grinding disc. 
 
     
     
       2. The agitator mill according to  claim 1 , wherein said first grinding disc further comprises a plurality of slots each positioned radially outward from said rotatable shaft and radially inward from said peripheral edge of said first grinding disc, wherein said axially extending pin is located in a disc segment between said plurality of slots. 
     
     
       3. The agitator mill according to  claim 2 , wherein said first grinding disc has a center and an outer periphery and said plurality of slots that are positioned equidistant from said center to form a slot circle having an inner diameter and an outer diameter. 
     
     
       4. The agitator mill according to  claim 3 , wherein said plurality of slots are three slots. 
     
     
       5. The agitator mill according to  claim 3 , wherein said plurality of slots are four slots. 
     
     
       6. The agitator mill according to  claim 4 , wherein said three slots are kidney shaped. 
     
     
       7. The agitator mill according to  claim 4 , wherein said axially extending pins are located closer to the outer periphery than the center. 
     
     
       8. The agitator mill according to  claim 4 , wherein said first grinding disc further comprises second, third and fourth axially extending pins, wherein said first and second axially extending pins are located on a first side of said grinding disc and are spaced approximately 180 degrees apart and said third and fourth pin are located on a second, opposite side of said first grinding disc and are spaced approximately 180 degrees apart and wherein said third pin is offset about 90 degrees from said first pin and said fourth pin is offset about 90 degrees from said second pin. 
     
     
       9. The agitator mill according to  claim 8 , wherein each of said first, second, third, and fourth axially extending pins are positioned on a disc segment located between one of the at least first, second and third slots, and each of said axially extending pins are offset radially outwardly from the outside diameter defined by said slots. 
     
     
       10. An agitator mill according to  claim 8 , wherein said first, second, third and fourth axial pins are positioned equidistant from the center and define a circular path along the first and second sides of said first grinding disc. 
     
     
       11. The agitator mill according to  claim 10 , wherein said circular path has a diameter ranging from approximately 75% to approximately 90% of the outer diameter of the disc. 
     
     
       12. The agitator mill according to  claim 11 , wherein said circular path diameter ranges from approximately 85% to approximately 87% of the outer diameter of the disc. 
     
     
       13. The agitator mill according to  claim 8 , wherein said axially extending pins each have a protrusion height that ranges from approximately 8% to approximately 15% of a difference between the outer diameter of the disc and the inner diameter of the slot circle. 
     
     
       14. The agitator mill according to  claim 13 , wherein the protrusion height ranges from approximately 11% to approximately 12% of the difference between the outer diameter of the first grinding disc and inner diameter of the slot circle. 
     
     
       15. The agitator mill according to  claim 13 , wherein said axially extending pins have a diameter ranging from approximately 90% to approximately 110% of the protrusion height. 
     
     
       16. The agitator mill according to  claim 15 , wherein said axially extending pins has a diameter that ranges from approximately 105% to approximately 107% of the protrusion height. 
     
     
       17. An agitator mill for grinding a product, comprising:
 a housing having a first end and a second end; 
 a rotatable axial shaft disposed within said housing that extends at least partially between said first end and said second end; 
 a first grinding disc having a peripheral edge and an outer diameter connected to said shaft in a generally perpendicular orientation, wherein said first grinding disc comprises a first axially extending pin positioned radially outward from said rotatable shaft and radially inward from said peripheral edge of said first grinding disc; 
 a second grinding disc having a peripheral edge connected to said shaft in a generally perpendicular orientation at a spaced apart distance from said first grinding disc; and 
 grinding media that grinds the product disposed within said housing, 
 wherein said first axially extending pin is aligned with a smooth surface of said second grinding disc. 
 
     
     
       18. The agitator mill according to  claim 17 , wherein said first grinding disc further comprises a plurality of slots each positioned radially outward from said rotatable shaft and radially inward from said peripheral edge of said first grinding disc, wherein said axially extending pin is located in a disc segment between said plurality of slots. 
     
     
       19. The agitator mill according to  claim 18 , wherein said first grinding disc has a center and an outer periphery and said plurality of slots that are positioned equidistant from said center to form a slot circle having an inner diameter and an outer diameter. 
     
     
       20. The agitator mill according to  claim 19 , wherein said plurality of slots are four slots. 
     
     
       21. The agitator mill according to  claim 20 , wherein said four slots are kidney shaped. 
     
     
       22. The agitator mill according to  claim 20 , wherein said axially extending pins are located closer to the outer periphery than the center. 
     
     
       23. The agitator mill according to  claim 20 , wherein said first grinding disc further comprises second, third and fourth axially extending pins, wherein said first and second axially extending pins are located on a first side of said grinding disc and are spaced approximately 180 degrees apart and said third and fourth pins are located on a second, opposite side of said first grinding disc and are spaced approximately 180 degrees apart and wherein said third pin is offset about 90 degrees from said first pin and said fourth pin is offset about 90 degrees from said second pin. 
     
     
       24. The agitator mill according to  claim 23 , wherein each of said first, second, third, and fourth axially extending pins are positioned on a disc segment located between one of the at least first, second, third, and fourth slots, and each of said axially extending pins is offset radially outwardly from the outside diameter defined by said slots. 
     
     
       25. An agitator mill according to  claim 23 , wherein said first, second, third and fourth axial pins are positioned equidistant from the center and define a circular path along the first and second sides of said first grinding disc. 
     
     
       26. A method for mixing or grinding a product in a mill having a rotatable shaft, comprising:
 combining the product with a grinding media to form a product-media mixture; 
 passing the product-media mixture through the mill; 
 rotating a plurality of grinding discs connected to the rotatable shaft, wherein at least one of the grinding discs has first, second, third and fourth axially extending pins located on the at least one grinding disc, wherein the first and second axially extending pins extend from a first side of the at least one disc, and wherein the third and fourth axially extending pins extend from a second side of the at least one disc, wherein the first and second axially extending pins are spaced apart radially approximately 180°, and the third and fourth axially extending pins are spaced apart radially approximately 180°, and are offset from the first and second axially extending pins by approximately 90°, and wherein the axially extending pins being located in a radial position between four elongate arcuate slots; and 
 discharging the product from the mill. 
 
     
     
       27. A grinding disc for use with an agitator mill that agitates and grinds a product, comprising:
 a peripheral edge; 
 a central opening for attachment to a rotatable shaft; 
 an outer diameter; 
 a first axially extending pin positioned radially outward from said central opening and radially inward from said peripheral edge of the grinding disc; 
 a second axially extending pin positioned radially outward from said central opening and radially inward from said peripheral edge of the grinding disc, wherein said second axially extending pin is spaced approximately 180 degrees apart from said first axially extending pin; and 
 a plurality of slots each positioned radially outward from said central opening and radially inward from said peripheral edge of the disc, wherein said first and second axially extending pins are located in a disc segment between said plurality of slots, 
 wherein said first axially extending pin and said second axially extending pin combine with a grinding media to grind the product.